Copper(ii)-catalyzed synthesis of sulfonyl-functionalized quinone-fused cyclopenta[b]indoles via four-component cascade annulation

Abstract

A copper-catalyzed four-component cascade annulation is realized to access novel sulfonyl-functionalized quinone-fused cyclopenta[b]indoles with high step economy and broad substrate scope, and 34 examples are constructed in one pot with up to 88% yield. This process includes sulfonyl radical triggered tandem cyclization by selective 1,1,2-trifunctionalization of terminal acetylene.